Comment by cperciva | Hacker News Reader

Comment by cperciva | Hacker News Reader

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From the article:

the newest report has Netflix at 9.48 percent of upstream and 34.89 percent of downstream [...] The average Internet subscribing household in North America uploaded 7.6GB of data per month in Sandvine's report in the first half of this year, increasing to 8.5GB in the latest report, a boost of 11.8 percent. The average household's monthly downloads increased from 43.8GB to 48.9GB, a boost of 11.6 percent.

So the average "Internet subscribing household in North America" downloads 48.9GB * 34.89% = 17.1 GB from Netflix, and uploads 8.5GB * 9.48% = 0.8 GB. If the upstream is all 40 byte ACKs, that's one ACK per 850 bytes downloaded, which is a bit more ACKing than I expected, but not completely unreasonable.

This seems high and would seem to amount to an ACK for almost every second downstream packet. Since I pcap ALL THE THINGS, I looked at some Netflix streaming sessions from a 3 different clients over a week.

Stream 1: 43MB down, 21KB up

Stream 2: 56MB down, 28KB up

Stream 3: 126MB down, 62KB up

That's using Wireshark to count the bytes in the TCP conversation.

Don't forget the retransmissions due to the under-provisioned links to Level3 networks by some companies who are currently (or have in the past) extorted money out of Netflix.

I'm sure you are aware of this, but the average here seems missleading. The median household has never Torrented anything, therefore I think that the median would be more representative of the average user's habits.

yeah but by averaging the upload and averaging the download and just finding the ratio of the two he's not really substantially affecting his argument vs. using the median, right?

The median would be much lower than the average.

Maybe people should listen to statistician's main lament about number in the press :

Will you please start including the standard deviation ?

Would contain a lot more information than just having mean and median.

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